Business Combinations and Divestitures (Details 3) (USD $) In Millions, unless otherwise specified	9 Months Ended	1 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Mar. 31, 2011 Carter Machinery Company Inc Country	Mar. 31, 2011 Carter Machinery Company Inc Cat Financial
Disposal groups including discontinued operations
Percentage of equity interest of subsidiary sold (as a percent)			100.00%
Net amount of sale of interest in subsidiary			$ 358
Number of counties in which Carter Machinery operated			9
Financing provided to buyer	7,091	6,121		348
Pre-tax gain from divestiture			$ 18

Represents net amount related to divestitures of business.

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Represent number of counties in which Carter Machinery has operations and stores.

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Represents percentage of interest in subsidiary sold by the reporting entity during the period.

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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The cash outflow for the purchase of amounts due from customers, clients, lessees, borrowers, or others under the terms of its agreements therewith.

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